(a) Field of the Invention
The present invention relates to a yarn-changing method in a warping machine with yarn changing units, particularly to an automatic yarn-changing and color-changing method in a warping machine with yarn changing units.
(b) Description of the Prior Art
Generally speaking, in the conventional preparation of sample fabrics for customers in the textile industry, it is necessary to cut several yarns at the same length from yarn packages with reference to the required length and quantity of yarns. If ten thousand yarns are needed, ten yarn packages are used, such that when working each yarn package by the same operations for one thousand times, ten thousand yarns can be made. Then these ten thousand yarns at the same length are wound around a warp beam to form the warp required for weaving. This step is called a warping step. Finally, the warp is crisscross woven with a woof to form knitted fabrics. Therefore, the warping step is the most important procedure in the warp preparation process. This step is to wind a plurality of warps at a specified length horizontally around a warp beam at a specified working width. Consequently, the main objective of the warping procedure is to make the tension of all the warps wound on the warp beam uniform and constant without changes in the entire warping process; otherwise, this will cause broken ends during the weaving process and inaccurate fabric structures. Moreover, this procedure also makes all the warps evenly and horizontally arranged on the warp beam in order to make the warp beam accurately wound into a cylindrical shape, avoid the wearing of warps in the entire warping procedure, maintain the physical and mechanical properties of warps, and enhance the production efficiency of the warping machine as far as possible.
However, due to the limitation of the machine, drawbacks are inherent in the conventional warping method. They are: (1) it fails to ensure uniform warp tension or (2) it fails to ensure uniform warp tension during the entire yarn package unwinding process. In fact, the creel structure in the warping machine is required to achieve uniform tension, winding, and arrangement. Generally speaking, creels can be classified into rotary creels, flat creels, and composite creels comprising both rotary creels and flat creels. However, during operations, the working of the warping machine is limited by the working of the creel, thereby unable to be efficiently applied. For conventional warping machines having creels, although rotary creels are at high speed and can process a plurality of yarns simultaneously, they remain to be limited by their creel structures, thereby unable to change yarn and yarn color automatically. To perform the color-changing process, on the one hand, it is required to stop the machine and perform the color-changing preparations. Therefore, it is time consuming. On the other hand, for conventional warping machines having flat creels, the working of flat creels is slower, such that only one yarn can be prepared for color changing at one time. Although it is easy to change yarn color for flat creels, they are less efficient. If the aforementioned composite creel comprising both the rotary creel and flat creel are independently set up, the rotary and flat creel simultaneously work together, such that during color changing, it is required to lower the speed of the machine and choose only one color as the primary color. Moreover, it is even more time consuming to change the creel, thereby failing to effectively perform the color-changing process.
Consequently, the object is to develop an integrated yarn-changing method in a warping machine having yarn changing units, thereby enhancing the efficiency of the yarn-changing procedure for the entire warping machine, speeding up the warping process, and changing yarns and yarn color more efficiently.